Due to the rapid increase of smart-phone usage, data traffic on mobile networks has experienced explosive growth. Data streaming (such as video streaming) represents a significant part of data traffic. According to some estimates, video streaming accounts for 39% of mobile data traffic, and will account for about 70% of all mobile data traffic by 2016. In view of this trend, methods for data streaming are subject to continuing study and development.
P2P is a popular method of data streaming. Some P2P-based streaming systems have being quite successful in the context of fixed access networks. For example, a peer-to-peer streaming video network created at Huazhong University of Science and Technology in China (PPlive) is estimated to have about 110 million users, 2 million concurrent online peers, and over 600 channels. In another example, Chinese peer-to-peer streaming video network software, PPstream, has been installed on about 350 million devices and is used daily by about 12 million users. Most P2P-based streaming systems are quite scalable by making use of uplink (UL) contribution from a large number of peers. Due to the advantages of P2P systems, several leading Content Distribution Network (CDN) manufacturers, such as Akamai, have started to implement P2P capabilities in their CDN systems.
Conventional P2P-based streaming systems used in fixed networks face some serious problems in mobile networks. For example, UL transmissions from mobile user equipment (UE) consume a lot of power, and the P2P system heavily uses UL transmissions from peers. Additionally, in typical P2P-based streaming systems, a large number peers exchange a large number of P2P signaling messages besides data packages. P2P signaling messages (exchanged very frequently, e.g., 1-10 ms, with an average IP packet size of less than 100 bytes) have been observed to be quite harmful to mobile networks.
MBMS is a point-to-multipoint method for data service in 3GPP mobile networks like 3G and LTE used to provide data services to a large number of user equipments which may be mobile. In fact, MBMS may have plural other functions (streaming being only one of them) serving a large number of UEs. MBMS can be used to simultaneously stream the same content to multiple mobile users in the same area by broadcast over radio interface, thereby saving radio resource and avoiding high power consumption. However, if the number of users streaming the same content becomes small, MBMS will not be radio resource efficient.
The number of mobile peers located in one or more LTE cells in the same broadcasting area receiving the same streaming content may change dynamically. For example, in a conventional P2P system 100 as illustrated in FIG. 1, sometimes only one or two of the peers 101a-101d in an LTE cell 110 receive the same streaming content (e.g., from the channel server 130 or from peer 101e via interface 140), while at other times, tens of peers in the same LTE cell 110 are receiving the same content. The content sources may be connected via the Internet rather than the core network 120 directly. Although the core network 120 may be configured to provide MBMS services, conventionally, it is not possible to optimize resource usage (i.e., saving downlink (DL) LTE resources or not overloading radio interfaces) by considering the number of peers receiving the same streamed content because P2P service is an Internet-based over-the-top (OTT) service which is usually independent of which operator owned MBMS system.
A mobile deputy module has been considered for deployment in a radio access network device of a core network (RAN) or at the edge of core network to optimize P2P system and make P2P system more friendly to mobile networks. As illustrated in FIG. 2, in a radio communication network system 200, the presence of the mobile deputy 205 splits the P2P system 200 into two parts: a simplified P2P portion and a normal portion. The deputy 205 acts as a proxy for all the peers inside the simplified P2P portion, being the only “neighbor” of the peers 201a-201d inside the simplified P2P portion. However, the P2P deputy operates only relative to streaming toward the peers in the simplified P2P portion (i.e., not retrieving streaming from mobile peers 201a-201d to peers in the normal network). The presence of the mobile deputy 205 results in avoiding UL contribution from mobile peers and significantly alleviates P2P signaling over radio links. However, one potential problem for the deputy is scalability, i.e., the deputy could be a potential bottleneck in the system when a large number of mobile peers in the simplified P2P portion are served simultaneously by the deputy. When the deputy is overloaded, it is likely that many peers are streaming the same P2P content (live streaming case), but the usage of DL is not optimized.
FIG. 3 illustrates a recently developed approach to optimizing load related to P2P live streaming, between a P2P live streaming network 320 (providing a P2P-based streaming service to peers 301a and 301b communicating via base stations 310a and 310b) and an access network 340. A node 325 operates in the streaming network 320 as a Mobile Cloud Accelerator Peer to Peer (MCAP2P).
If a peer 301a asks a tracker 330 to provide a list of peers streaming content related to an IPTV channel 1, the MC2 P2P node 325 intercepts peer 301a's request and increments a number of peers watching channel 1, storing the peer's ID. Peer 301a receives the list of peers, connects to these peers and starts using the P2P-based streamed content.
If then another peer 301b asks the tracker to provide the list of peers streaming content related to the IPTV channel 1, the MC2 P2P node 325 intercepts peer 301b's request and identifies that more than a predetermined number of peers T (which is set by MNO) are already streaming content related to the IPTV channel 1. Then, the MC2 P2P node 325 joins P2P network to receive content related to the IPTV channel 1 from selected sources. The MC2 P2P node 325 starts converting the P2P stream into an eMBMS format, and opens an eMBMS socket. Further, the MC2 P2P node 325 signals to all peers streaming content related to the IPTV channel 1 to switch from P2P (unicast) streaming and to connect to the eMBMS socket. The peers streaming content related to the IPTV channel 1 (e.g., peer 301a and peer 301b) stop P2P-based streaming, join a multicast tree and start receiving content related to the IPTV channel 1 via multicast form MC2 P2P node 325.
The MC2 P2P-based approach has the disadvantage that it requires the mobile network/MC2 P2P to intercept and analyze P2P related messages in order to estimate the numbers of peers streaming the same content. When the number users is large, analyzing the large number of P2P related messages becomes a challenge. Additionally, the P2P traffic may be encrypted.
Accordingly, it would be desirable to have methods and radio communication network systems able to provide streaming services to mobile users while optimizing network resource usage and avoiding bottlenecks.